Alternative and Hybrid Consensus Mechanisms BDC Practice Questions (Page 1)

Questions 1–5

1. 1application · medium

   A cross-chain bridge protocol needs a consensus mechanism that provides fast finality on the source chain to reduce bridge withdrawal times, but also wants to maintain the security guarantees of the underlying PoW chain. Which hybrid approach achieves this?

   • ASwitch the entire chain to pure Proof-of-Stake for faster finality
   • BRequire 100 block confirmations on the PoW chain before processing bridge withdrawals
   • CUse a sidechain with Proof-of-Authority and trust the sidechain validators
   • DUse a PoW chain with a checkpointing protocol where PoS validators finalize blocks every 100 blocks
   Reveal Solution Discussion Select an answer first
2. 2application · medium

   A developer is researching hybrid consensus mechanisms and wants to understand how Decred's model differs from a simple proof-of-stake system. Which key characteristic of Decred's hybrid is NOT present in a pure PoS system?

   • AThe protocol has a fixed block time
   • BBlock production is performed by proof-of-work miners, not by stakeholders
   • CStakeholders vote on governance proposals
   • DThe network uses a native token for transaction fees
   Reveal Solution Discussion Select an answer first
4. 3application · medium

   A developer is designing a new cryptocurrency and wants to combine the security of proof-of-work with the energy efficiency of proof-of-stake. They plan to use PoW for block production and PoS for finality. What is the primary purpose of the PoS finality layer?

   • ATo replace the need for PoW entirely
   • BTo increase the block reward for miners
   • CTo make the network permissioned
   • DTo provide a deterministic point after which transactions cannot be reverted
   Reveal Solution Discussion Select an answer first
5. 4application · medium

   A developer is building a private blockchain for a hospital network. They want to use a hybrid consensus that combines proof-of-authority for block production with proof-of-stake for voting on network upgrades. What is the primary benefit of this hybrid approach compared to using pure proof-of-authority?

   • AIt automatically increases the transaction throughput
   • BIt makes the network completely permissionless
   • CIt eliminates the need for any trusted validators
   • DIt gives a broader set of stakeholders a voice in governance decisions
   Reveal Solution Discussion Select an answer first
6. 5application · medium

   A developer is designing a hybrid consensus for a supply chain network. They want to combine proof-of-authority for block production with proof-of-stake for governance. What is the main reason to use PoA for block production instead of PoW?

   • APoA eliminates the need for any governance
   • BPoA provides faster block times and lower energy consumption, which is suitable for a permissioned network
   • CPoA allows anyone to become a validator without permission
   • DPoA makes the network fully decentralized
   Reveal Solution Discussion Select an answer first